BI110 Chapter 21: Module 21
Document Summary
Cascade of events within cell translates signals into cellular responses. Sequence of biochemical rxns w/ proteins = response. Chemical form, but heat or light can also activate receptors. Proteins not always active or always inactive activity must be turned on or off as necessary. Phosphate group transferred from atp, and binds to proteins. Adds negative charges which change shape as phosphate group repels atoms. Shape change modifies protein"s function example: enzymes active site = exposed or blocked by shape change. Diff combinations of phosphorylated + unphosphorylated amino acids in proteins allow control of function b/c each combination = unique shape = diff function. Kinases catalyze phosphorylation of proteins; specific to proteins. Having individual kinases to control activity of protein = flexibility & control over all cell activity. Phosphorylated protein in active form occasionally dep inactivates proteins. *kinase + phosphatases = phosphorylation cascade phosphorylation rxns drive signaling pathway. Plays role in development of cancers, diseases.
